Prior known restraint systems operate in response to sensors once the G-force or inertia thresholds (approximately 0.7 g's for seatbelts) required to activate the restraint system have been exceeded. Typically, seatbelt sensors are mechanical devices that activate the retractor, or more specifically, place the retractor in a "locked" position (no further webbing is allowed to pay out of the retractor once it has been locked). During normal airbag and pyrotechnic pretensioner (buckle or retractor) operation, these devices are operated according to a control program stored in memory that constantly monitors the operation and readiness of the restraint system, typically including a diagnostic routine that continually checks for any error signals from the sensors or other components of the restraint system indicating a component failure requiring repair, or other maintenance or service. While on-board diagnostics are desirable, continuous operation of the diagnostic routine during the normal operation of the vehicle restraint system controller requires the dedication of at least a portion of the processing time of the central processing unit to be allocated to the diagnostic routine rather than continuously monitoring the status of the sensors in preparation for activation of the restraint system to protect the occupants of the vehicle.